Toshiba 29VH27D, Service Manual

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23
•
4 MHz reference frequency input [signal from Phase-Locked Loop (PLL) tuning system] or operating as
crystal oscillator
•
VIF Automatic Gain Control (AGC) detector for gain control, operating as peak sync detector for negative
modulated signals and as a peak white detector for positive modulated signals
•
Precise fully digital Automatic Frequency Control (AFC) detector with 4-bit digital-to-analog converter; AFC
bits via I 2 C-bus readable
•
Take Over Point (TOP) adjustable via I 2 C-bus or alternatively with potentiometer
•
Fully integrated sound carrier trap for 4.5, 5.5, 6.0 and 6.5 MHz, controlled by FM-PLL oscillator
•
Sound IF (SIF) input for single reference Quasi Split Sound (QSS) mode (PLL controlled)
•
SIF AGC for gain controlled SIF amplifier; single reference QSS mixer able to operate in high performance
single reference QSS mode and in intercarrier mode, switchable via I 2 C-bus
•
AM demodulator without extra reference circuit
•
Alignment -free selective FM-PLL demodulator with high linearity and low noise
•
I 2 C-bus control for all functions
•
I 2 C-bus transceiver with pin programmable Module Address (MAD).
14.15.3.Pin Configurations
Symbol Pin Description
VIF1 1 VIF differential input 1
VIF2 2 VIF differential input 2
OP1 3 output 1 (open-collector)
FMPLL 4 FM-PLL for loop filter
DEEM
5
de-emphasis output for capacitor
AFD
6
AF decoupling input for capacitor
DGND 7 digital ground
AUD 8 audio output
TOP 9 tuner AGC TakeOver Point (TOP)
SDA 10 I 2 C-bus data input/output
SCL 11 I 2 C-bus clock input
SIOMAD 12 sound intercarrier output and MAD select
n.c 13 not connected
TAGC
14
tuner AGC output
REF
15
4 MHz crystal or reference input
VAGC 16 VIF-AGC for capacitor (Not connected for TDA9885.)
CVBS 17 video output
AGND 18 analog ground
VPLL 19 VIF-PLL for loop filter
VP
20 supply voltage (+5 V)
AFC 21 output
OP2
22
output 2 (open-collector)
SIF1
23
differential input 1
SIF2
24
differential input 2
14.16.LM7808
14.16.1.Description
The L7800 series of three-terminal positive regulators is available in TO -220 TO -220FP TO-3 and D 2
PAK packages and several fixed output voltages, making it useful in a wide range of applications.
These regulators can provide local on-card regulation, eliminating the distribution problems associated
with single point regulation. Each type employs internal current limiting, thermal shutdown and safe
area protection, making it essentially indestructible. If adequate heat sinking is provided, they can
deliver over 1A output current. Although designed primarily as fixed voltage regulators, these devices
can be used with external components to obtain adjustable voltages and currents.
14.16.2.Features
Output Current Up To 1.5 A
Output Voltages of 5; 5.2; 6; 8; 8.5; 9; 12; 15; 18; 24V
Thermal Over load protection
Short Circuit Protection
Output Transition SOA Protection